<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    .box{
        width: 300px;
        height: 100px;
        margin-top: 10px;
        margin-left: 20px;
        border: paleturquoise solid 1px;
        text-align: center;
        border-radius: 5px;
        box-shadow: 2px 2px 2px #ccc;
    }
    p{
        margin-top: 10px;
        margin-left: 20px;
    }
</style>
<body>
    
    <div id="app">
        <div class="box">
            <h3>小黑自动售卖机</h3>
            <button @click="buy(5)">可乐5元</button>
            <button @click="buy(10)">咖啡10元</button>
        </div>
        <p>银行卡余额：{{money}} 元</p>
        
    </div>

    <script src="https://cdn.jsdelivr.net/npm/vue@2.7.16/dist/vue.js"></script>
    <script>
        const app=new Vue({
            el:"#app",
            data:{
                money:100
            },
            methods:{
                //提供处理逻辑函数
                buy(price){
                    //让提供的所有methods中的函数，this都指向当前实例 实例代表初始化时的app
                    this.money-=price
                }
            }
        })
    </script>

</body>
</html>